Refrigerating unit



Jan. 22, 1957 g READ 2,7?8J9Q REFRIGERATING UNIT Filed May 1'7. 1955 [NVEN TOR. LEGNARDkiREAD ATTORNEY United States Patent REFRIGERATIN G UNIT Leonard H. Read, Hoxsie, R. 1. Application May 17, 1955, Serial No. 508,900 3 Claims. (Cl. 62-92) This invention relates to a refrigerating unit and more particularly to a refrigerating unit for use in moving vehicles.

A principal object of the present invention is to provide a refrigerating unit for use in moving vehicles such as boats, trailers and railroad refrigerating cars.

Another object of the present invention is to provide a refrigerating unit which uses liquid carbon dioxide as a refrigerant under the control of a unique valve.

And still another object of the present invention is to provide a refrigerating unit simple in construction, foolproof in operation and inexpensive to maintain.

Other objects of the present invention will be pointed out in part and become apparent in part in the following specification and claims.

In the past carbon dioxide has been used as a refrigerant. Applicant provides a unique structure which allows for two stages of expansion for the liquid carbon dioxide. Said unique structure provides for a water valve which controls the escape of the carbon dioxide refrigerant in direct relationship to the temperature surrounding the new and improved refrigerating unit.

Referring to the drawings in which similar characters of reference indicate corresponding parts in all the figures:

Figure l is a side elevational view of the new and improved refrigerating unit.

Figure 2 is a longitudinal sectional view taken along line 22 of Figure 1.

Figure 3 is a horizontal sectional view taken along line 3 3 of Figure 2.

Figure 4 is a top plan view of Figure 1.

Referring to the drawings wherein the new and improved refrigerating unit is indicated generally by the reference numeral 10. A copper tube 17 is provided as constituting an expansion chamber 12. A cap 21 provided with a projection 24 is secured to one end of tube 17. A counterbore 25 is provided axially in projection 24. A capillary opening is provided in cap 21 connecting counterbore 25 with expansion chamber 12.

A plug 16 is provided with two steps 26 and 27. Tube 17 engages step 27. A second short copper tube 15 slightly larger in diameter than tube 17 engages step 26. Tubes 17 and 15 are secured to plug 16 with a well 20 formed between said tubes 15 and 17. Four spacers 28 are fixed between tubes 15 and 17. Four capillary openings 18 are provided in the base end of tube 17 to provide a port between expansion chamber 12 and well 20. A plurality of fins 30 are fixed to tube 17.

In operation water will be placed in well 20. A conduit leading from a source of supply of liquefied gas will be attached to projection 24. Refrigerating unit will be placed in a box which is to be cooled. The liquid gas will pass into counter-bore 25 and through capillary opening 11 into expansion chamber 12 where the liquid gas will expand by absorbing heat and thereby cool tube 17. Through conduction fins 30 will be cooled. The liquid gas which now is vaporized will pass through capillary openings 18 into and through the water in well 20 and pass into the atmosphere to be lost. After passing through capillary openings 18 the vapor further expands. In passing through the water, the vapor will freeze the water thereby creating a valve which will plug capillary openings 18 to prevent the further escape of vapor. As fins 30 and tube 17 absorb heat and as the atmosphere surrounding refrigerating unit 10 warms u the ice in well 20 will melt permitting the escape of vapor through the water in well 20. As the vapor passes through the water it will again freeze the water to again plug capillary openings 18. Thus a cycle is endlessly established. The cycle obviously depends upon a source of supply of liquefied gas and water in well 20.

Having shown and described a preferred embodiment of the present invention, by way of example, but realizing that structural changes could be made and other examples given without departing from either the spirit or scope of this invention.

What I claim is:

1. In a refrigerating unit utilizing a liquefied gas as a refrigerant, the combination of an expansion chamber, a cap provided on one end of said expansion chamber, a capillary opening in said cap leading into said chamber from the source of supply of a liquefied gas, a plug secured to the other end of said expansion chamber, a tube secured to said plug and radially spaced from said expansion chamber to provide a well and a plurality of capillary openings leading from said expansion chamber to said well said liquefied gas having a first stage of expansion after passing through said first mentioned capillary opening and into said chamber and a second stage of expansion after passing through said plurality of capillary openings and into said well, water in said well, said water acting as a valve to stop the flow of gas through said plurality of capillary openings as said gas passing through said water freezes said Water.

2. in a refrigerating unit utilizing a liquefied gas as a refrigerant, the combination of a first tube constituting an expansion chamber, a cap provided with a projection secured to one end of said first tube, means to secure a conduit leading from the source of supply of a liquefied gas to said projection, a capillary opening in said cap connecting said conduit with said expansion chamber, a plug secured to the other end of said first tube, a second tube secured to said plug and spaced radially from said first tube to provide a well between said first tube and said second tube and a plurality of capillary opening in said first tube to provide escape ports from said expansion chamber to said well said liquefied gas having a first stage of expansion after passing through said first mentioned capillary opening and into said chamber and a second stage of expansion after passing through said plurality of capillary openings and into said well, water in said well, said water acting as a valve to stop the flow of gas through said plurality of capillary openings as said gas passing through said water freezes said water.

3. In a refrigerating unit utilizing a liquefied gas as a refrigerant, the combination of a first tube constituting an expansion chamber, a plurality of fins secured to said first tube, a cap provided with a projection being secured to one end of said first tube, a capillary opening in said cap, a plug secured to the other end of said first tube, a second tube secured to said plug and spaced radially from said first tube to provide a well between said first and said second tubes, a plurality of capillary openings in said first tube connecting said well with said expansion chamber, means to secure a conduit leading from the source of supply of a liquefied gas to said projection, water in said well, the liquefied gas passing from said conduit to and through said capillary opening whereby said liquefied gas passing into said expansion chamber absorbs heat,

cooling said first tube and expanding into a gaseous state, References Cited in the file of this patent the gas passing through said plurality of capillary opening into said well and into said water, whereby said Hater UNITED STATES PATENTS freezes into a solid blocking said plurality of capi ary openings, as said first tube absorbs heat, said ice will 5 g melt permitting the gas to pass through said plurality of 1980156 g E 1934 capillary openings to again freeze said water into a solid mnc state to again block the passage of gas through said plurality of capillary openings. 

